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Benzodiazepine intermediates for the preparation of imidazobenzodiazepines

US 4,257,946 A · Assignee: Hoffmann-La Roche Inc. · Inventors: Walser; Armin

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed February 21, 1980 and granted March 24, 1981. A patent filed before June 8, 1995 lasts 17 years from grant or 20 from filing, whichever is longer, so its term ended February 21, 2000.
  • Any extension is capped at five years, so it can't still be in force.
  • We haven't checked its US family, and a later related patent could still be in force. We check US rights only.
FiledFebruary 21, 1980
GrantedMarch 24, 1981
Term endedFebruary 21, 2000
Application number06/123525
Classification (CPC)C07D487/04 +1 more
Length8 pages

Timeline

Timeline From USPTO dates

1981198319851987198919911993199519971999Application filedFeb 21, 1980Patent grantedMarch 24, 1981Term endedFeb 21, 2000

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